Strapping tool

ABSTRACT

A strapping tool includes a main body, a strap winding device, and a strap cutting device. The main body is pivotally provided with a first engaging member. The strap winding device includes a spindle. The spindle is provided with a handle, a ratchet gear and a stopper. The handle is pivotally connected with a second engaging member and a push member. When the strapping tool is in a return state, the push member pushes the first engaging member so that the first engaging member disengages from the ratchet gear and the second engaging block leans against the stopper for the user to rotate the spindle freely so as to insert or remove a packing strap.

FIELD OF THE INVENTION

The present invention relates to a strapping tool.

BACKGROUND OF THE INVENTION

A packing strap is always used to pack goods through a manual strappingtool for transportation. A conventional strapping tool comprises a mainbody. The main body is provided with a cutting device, a strap windingdevice, and a strap pressing device. The strap winding device isprovided with a handle. After the packing strap is wound around anarticle to be packed, one end of the packing strap is inserted throughthe strap pressing device, the other end of the packing strap isinserted through the cutting device and wound around the strap windingdevice, and then the packing strap is gradually tightened by the handle.Finally, the unnecessary packing strap is cut by the cutting device tocomplete the packaging operation.

When the packing strap is tightened by the handle, the packing strapexerts a counterforce on the strap winding device, causing the handle tobe stuck and unable to rotate. In this situation, it is required toscissor the packing strap, and then the packing operation is performedagain. When the strap winding device is wound with the excessive packingstrap and the good is not tightened, the cutting device is used to cutthe packing strap and then the packing operation is performed again. Theconventional strapping tool cannot achieve the effect of quick packing.Accordingly, the inventor of the present invention has devoted himselfbased on his many years of practical experiences to solve theseproblems.

SUMMARY OF THE INVENTION

The primary object of the present invention is to provide a strappingtool which allows the user to freely rotate a spindle for a quick andeffortless packing when in a return state.

In order to achieve the aforesaid object, the strapping tool of thepresent invention comprises a main body, a strap winding device, a strapcutting device, and a strap pressing device. The main body includes apress plate. The main body is pivotally provided with a first engagingmember. The first engaging member includes a first engaging block and apress block. The strap winding device includes a spindle. The spindle isprovided with a handle and a ratchet gear. The handle is pivotallyconnected with a second engaging member. The second engaging memberincludes a second engaging block. The handle is provided with a linkingmember and a push member. The strap winding device further includes astopper. The strap cutting device includes a cutter shaft. The cuttershaft is provided with a cutter tube and a connecting block. Theconnecting block is connected with the linking member. The strappressing device includes a strap pressing shaft. A first side of thestrap pressing shaft is provided with a cam. A second side of the strappressing shaft is provided with a strap pressing seat. The strappressing seat is pivotally connected with a strap pressing block.

When the strapping tool of the present invention is in a return state,the push member pushes the press block so that the first engaging blockdisengages from the ratchet gear and the second engaging block leansagainst the stopper for the user to rotate the spindle freely so as toinsert or remove a packing strap.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view in accordance with a first embodiment ofthe present invention;

FIG. 2 is a partial exploded view in accordance with the firstembodiment of the present invention;

FIG. 3 is a schematic view in accordance with the first embodiment ofthe present invention;

FIG. 4 is a schematic view in accordance with the first embodiment ofthe present invention, showing that the ratchet gear can be rotatedfreely when the handle is in a return state;

FIG. 5 is a schematic view in accordance with the first embodiment ofthe present invention, showing that the handle is operated to tightenthe packing strap;

FIG. 6 is a schematic view in accordance with the first embodiment ofthe present invention, showing that the first engaging member and thesecond engaging member engage with the ratchet gear;

FIG. 7 is a schematic view in accordance with the first embodiment ofthe present invention, showing that the pull block is pulled;

FIG. 8 is a schematic view in accordance with the first embodiment ofthe present invention, showing that the handle is pressed down;

FIG. 9 is a schematic view in accordance with the first embodiment ofthe present invention, showing that the handle drives the spindle;

FIG. 10 is a schematic view in accordance with the first embodiment ofthe present invention, showing that the handle drives the spindle torotate;

FIG. 11 is a schematic view in accordance with the first embodiment ofthe present invention, showing that the handle drives the spindle toreturn;

FIG. 12 is a schematic view in accordance with the first embodiment ofthe present invention, showing that the spindle is returned to theinitial position;

FIG. 13 is a schematic view in accordance with the first embodiment ofthe present invention, showing that the strap pressing seat, strappressing block and the spindle are replaceable;

FIG. 14 is a partial perspective view in accordance with a secondembodiment of the present invention, showing the first frame and thesecond frame;

FIG. 15 is a schematic view in accordance with the second embodiment ofthe present invention when in use, showing that the packing strap is ina tight state;

FIG. 16 is a side view in accordance with the second embodiment of thepresent invention, showing the second angle;

FIG. 17 is a schematic view in accordance with the second embodiment ofthe present invention when in use, showing that the packing strap is ina tight state; and

FIG. 18 is a schematic view in accordance with the second embodiment ofthe present invention when in use, showing that the strap pressing blockis pressed against the packing strap.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Embodiments of the present invention will now be described, by way ofexample only, with reference to the accompanying drawings.

As shown in FIG. 1 and FIG. 2, the present invention discloses astrapping tool 100. The strapping tool 100 comprises a main body 10, astrap winding device 20, a strap cutting device 30, and a strap pressingdevice 40.

The main body 10 comprises a first frame 11 and a second frame 12. Thefirst frame 11 is made of iron. The second frame 12 is made of aluminum.The first frame 11 is provided with a press plate 13. A first angle a isdefined between a top surface and a bottom surface of the press plate13, as shown in FIG. 3. The first angle a is in the range of 2-6degrees. A pivot 14 is insertedly mounted in the second frame 12. Thepivot 14 is provided with two first engaging members 141 and two springs142. Two ends of each spring 142 leans against the second frame 12 and acorresponding one of the first engaging members 141, respectively. Thetwo first engaging members 141 each include a first engaging block 143and a press block 144. The first engaging blocks 143 of the two firstengaging members 141 have different lengths, as shown in FIG. 10. Arecess 145 is defined between the first engaging block 143 and the pressblock 144. The second frame 12 of the main body 10 is further providedwith a positioning member 15. The positioning member 15 is a set screw.

The strap winding device 20 includes a spindle 21 insertedly mounted inthe first frame 11 and the second frame 12. The spindle 21 is providedwith a handle 22, a ratchet gear 23, a stopper 24, and an linking member25. The handle 22 is made of aluminum. The handle 22 is pivotallyconnected with a second engaging member 221. The second engaging member221 is pivotally connected to the handle 22 through a pin 222. Anelastic member 223 is provided to lean against the handle 22 and thesecond engaging member 221. The second engaging member 221 includes asecond engaging block 224 and a pull block 225. The pull block 225extends out of the handle 22. The pull block 225 engages with theratchet gear 23 in a normal state, as shown in FIG. 6. When the pullblock 225 is pulled, the pull block 225 disengages from the ratchet gear23, as shown in FIG. 7. The handle 22 is provided with a push member226. The push member 226 is inserted through a push axle of the handle22. When the handle 22 is in a return state, the push member 226 pushesthe two press blocks 144 so that the two first engaging blocks 43disengage from the ratchet gear 23, as shown in FIG. 4. When the handle22 is pressed down, the push member 226 is located in the two recesses145 so that the two first engaging blocks 143 disengage from the ratchetgear 23, as shown in FIG. 9. One end of the stopper 24 is secured to thesecond frame 12. The stopper 24 includes a stop block 241. The stopblock 241 is located between the second engaging member 221 and theratchet gear 23. When the handle 22 is in the return state, the secondengaging member 221 leans against the stop block 241, as shown in FIG.4. The handle 22 is provided with a linking pin 227. The linking pin 227is connected with the linking member 25, such that the handle 22 canlink the linking member 25 to turn. The linking member 25 includes afirst lifting portion 251 and a first return portion 252. The firstreturn portion 252 is an arc-shaped block.

The strap cutting device 30 includes a cutter shaft 31. The cutter shaft31 is provided with a cutter tube 32 and a connecting block 33. Theconnecting block 33 includes a second lifting portion 331 and a secondreturn portion 332 corresponding to the first lifting portion 251 andthe first return portion 252. The second return portion 332 is anarc-shaped block.

The strap pressing device 40 includes a strap pressing shaft 41. Thestrap pressing shaft 41 is insertedly mounted in the first frame 11 andthe second frame 12. A first side of the strap pressing shaft 41 isprovided with a cam 42 and an elastic member 43. The cam 42 is providedwith an extension rod 421. The extension rod 421 is pivotally providedwith a roller 422. Two ends of the elastic member 43 lean against thefirst frame 11 and the cam 42, respectively. A second side of the strappressing shaft 41 is integrally provided with an eccentric shaft 44. Theeccentric shaft 44 extends out of the second frame 12. The eccentricshaft 44 is sleeved with an elastic member 45 and a strap pressing seat46. Two ends of the elastic member 45 lean against the first frame 11and the strap pressing seat 46, respectively. The strap pressing seat 46has a mounting hole 461 therein, and is mounted to the eccentric shaft44 through a mounting member 462. The strap pressing seat 46 is providedwith a pivot shaft 463. The pivot shaft 463 is insertedly mounted in thestrap pressing seat 46 and pivotally connected with a strap pressingblock 47. The strap pressing seat 46 is provided with an elastic member464 at one side of the pivot shaft 463. The elastic member 464 is acompression spring. The other end of the elastic member 464 is pushedagainst the strap pressing block 47, as shown in FIG. 3.

In this present embodiment of the present invention, only the elasticmember 464 is a compression spring, and the other elastic members aretorsion springs.

Referring to FIG. 3, when the strapping tool 100 of the presentinvention is used to pack an article 200 with a packing strap 201, thehandle 22 is pressed down to drive the cam 42 to turn via the roller 422in cooperation with the extension rod 421. The strap pressing shaft 41is rotated to rotate the eccentric shaft 44 synchronously, therebylifting the strap pressing seat 46 and the strap pressing block 47. Asshown in FIG. 9, the packing strap 201 is inserted into the gap betweenthe strap pressing block 47 and the press plate 13 by the user, and thenthe handle 22 is released to lean against the roller 422 so that thehandle 22 is returned to press the packing strap 201.

Then, the free end of the packing strap 201 passes through the cuttershaft 31 and the spindle 21. When the handle 22 is returned, referringto FIG. 4, the push member 226 pushes the two press blocks 144 so thatthe two first engaging blocks 143 disengage from the ratchet gear 23,and the second engaging block 224 leans against the stop block 241 sothat the second engaging block 224 disengages from the ratchet gear 23,allowing the user to freely rotate the spindle 21 so that the packingstrap 201 can be easily inserted and secured.

Referring to FIG. 5 and FIG. 6, when the handle 22 is lifted up, thesecond engaging block 224 engages with the ratchet gear 23 to drive theratchet gear 23 to rotate the spindle 21 and to roll the packing strap201. When the handle 22 is pulled back, the two first engaging blocks143 engage with the ratchet gear 23. The two first engaging blocks 143have different lengths to engage with the ratchet gear 23 surely,preventing the ratchet gear 23 from reversing. Thereby, the handle 22 isrepeatedly operated to tighten the packing strap 201.

Referring to FIG. 7, when the packing strap 20 is tightened to a certaindegree and the handle 22 cannot be rotated, for example, the position ofthe handle 22 is not easy to exert a force or the counterforce of thepacking strap 201 causes the second engaging member 221 to be stuck withthe ratchet gear 23, the user can pull the pull block 225 to disengagethe second engaging block 224 from the ratchet gear 23, such that theuser can freely adjust the angle of the handle 22 to apply a force forfurther tightening the packing strap 201. In addition, when the spindle21 is wound with the excessive packing strap 201 and the article is nottightened, the user can operate the handle 22 to be in the return state,so that the two first engaging blocks 143 and the second engaging block224 disengage from the ratchet gear 23 for the user to rotate thespindle 21 freely to loosen the packing strap 201. The forgoing packingstep is operated again to tighten the packing strap 201.

Referring to FIG. 8, FIG. 9, and FIG. 10, finally, the handle 22 ispressed down, enabling the first lifting portion 251 to get contact withthe second lifting portion 331 to rotate the cutter shaft 31 so as tocut the packing strap 201. Meanwhile, the push member 226 is in the tworecesses 145 so that the two first engaging blocks 143 disengage fromthe ratchet gear 23, and the second engaging block 224 leans against thestop block 241 so that the second engaging block 224 disengages from theratchet gear 23 for the spindle 21 to be rotated freely to remove thepacking strap 201. The cam 42 is pressed down by the handle 22 to liftthe strap pressing seat 46 and the strap pressing block 47 to releasethe strap pressing state so that the packing operation is completed. Asshown in FIG. 11 and FIG. 12, the user may lift the handle 22 up for thefirst return portion 252 to get contact with the second return portion332 in a tangential state. Finally, when the cutter shaft 31 leansagainst the positioning member 15, the cutter shaft 31 is turned back tothe initial position.

It is worth mentioning that through the extension rod 421 and theeccentric shaft 44, the handle 22 can be rotated for a small angle tolift the strap pressing seat 46 and the strap pressing block 47. Whenthe strap pressing device 40 is operated to press the packing strap, theelastic member 464 enables the strap pressing block 47 to press thepacking strap 201 and the press plate 13. The first angle a definedbetween the top surface and the bottom surface of the press plate 13enables the strap winding device 20 to pull the packing strap 201.Therefore, the packing strap 201 is pulled to move rearward and thestrap pressing block 47 is driven to press the packing strap 201 and thepress plate 13, thereby enhancing the pressing capacity. The first anglea is in the range of 2-6 degrees, so that the strapping tool can be usedfor different thicknesses of packing straps.

Referring to FIG. 13, the mounting member 462 can be disassembled fromthe strap pressing device 40 by a wrench to replace the strap pressingseat 46 and the strap pressing block 47 quickly, alternatively, thepivot shaft 463 is removed manually to replace the strap pressing block47 quickly. Thereby, the strapping tool can be used for different typesof packing straps. Furthermore, the cutter shaft 31 may be in a halfmoon shape to improve the cutting efficiency.

The spindle 21 and the strap pressing shaft 41 are insertedly mounted inthe first frame 11 and the second frame 12 to position and secure thefirst frame 11 and the second frame 12. The first frame 11 is made ofiron, so that it can withstand the force generated during the packingprocess. The second frame 12 and the handle 22 are made of aluminum, sothat the weight can be reduced and the strapping tool can be operatedconveniently.

FIG. 14 is a partial perspective view in accordance with a secondembodiment of the present invention. The second embodiment issubstantially similar to the first embodiment with the exceptionsdescribed hereinafter. The top surface 131 and the bottom surface 132 ofthe press plate 13 are not parallel. In this embodiment, the top surface131 of the press plate 13 is an oblique surface. The top surface 131 ofthe press plate 13 is quadrangular. The top surface 131 has two firstsides 133 and two second sides 134. Referring to FIG. 15, when thepacking strap 201 is tightened, the moving direction of the packingstrap 201 located between the strap pressing block 47 and the pressplate 13 is parallel to the first sides 133. The first angle a isdefined between the first side 133 and the bottom surface 132. The firstangle a is in the range of 2-6 degrees, so that the top surface 131 isinclined upward from a positon close to the strap winding device 20toward a position close to the strap pressing device 40. As shown inFIG. 16, a second angle b is defined between the second side 134 and thebottom surface 132. The second angle b is in the range of 88-89.5degrees, so that the top surface 131 is inclined upward from a positonclose to the first frame 11 toward a position away from the strappressing device 40. Referring to FIG. 17, the packing strap 201 ispulled to be in a tight state. Seen in a longitudinal cross-sectionalview, the width direction of the packing strap 201 is parallel to thebottom surface 132. A third angle c is defined between the second side134 and the width direction of the packing strap 201. The widthdirection of the packing strap 201 is perpendicular to a direction thatthe packing strap 201 is applied with a force to move. The third angle cis in the range of 0.5-2 degrees.

Thereby, when the packing strap 201 is rolled, the packing strap 201will be pulled to be tightened and tensioned. Due to the third angle c,a gap is formed between the packing strap 201 and the top surface 131 ofthe press plate 13, which can reduce the contact area, reduce theresistance, and increase the packing efficiency, as shown in FIG. 16.

As shown in FIG. 15 and FIG. 18, when the strap pressing block 47presses the packing strap 201 against the press plate 13, the packingstrap 201 is forced to move backward, and the strap pressing block 47 ismoved backward to further press the packing strap 201 and the pressplate 13, so that the packing strap 201 can be inclined by the firstangle a and the second angle b. When the strap pressing block 47 ispressed against the packing strap 201, forces in different directionswill be generated to increase the resistance and avoid the packing strapfrom slipping. When the packing strap 201 passes through the press plate13, a turning point 202 is generated due to the first angle a, as shownin FIG. 15, which further increases the resistance and enhances theability to press the packing strap.

Although particular embodiments of the present invention have beendescribed in detail for purposes of illustration, various modificationsand enhancements may be made without departing from the spirit and scopeof the present invention. Accordingly, the present invention is not tobe limited except as by the appended claims.

What is claimed is:
 1. A strapping tool, comprising: a main body,including a press plate, the press plate having a top surface and abottom surface, a first angle and a second angle being defined betweenthe top surface and the bottom surface of the press plate; a strappressing device, including a strap pressing shaft, the strap pressingshaft being connected with a strap pressing block.
 2. The strapping toolas claimed in claim 1, wherein the first angle is in the range of 2-6degrees.
 3. The strapping tool as claimed in claim 1, wherein the secondangle is in the range of 88-89.5 degrees.
 4. The strapping tool asclaimed in claim 1, wherein the top surface has at least one first sideand at least one second side, the first angle is defined between thefirst side and the bottom surface, the first angle is in the range of2-6 degrees, the second angle is defined between the second side and thebottom surface, and the second angle is in the range of 88-89.5 degrees.5. The strapping tool as claimed in claim 1, wherein the main bodyincludes a first frame and a second frame, the first frame is made ofiron, the second frame is made of aluminum, and the first frame isprovided with the press plate.
 6. The strapping tool as claimed in claim1, wherein a packing strap is inserted between the press plate and thestrap pressing block, when the packing strap is in a tight state, athird angle is defined between the second side and a width direction ofthe packing strap, and the third angle is in the range of 0.5-2 degrees.7. The strapping tool as claimed in claim 1, wherein a first side of thestrap pressing shaft is provided with a cam, a second side of the strappressing shaft is provided with a strap pressing seat, and the strappressing seat is pivotally connected with the strap pressing block.